I allways thought that St. John of Lateran was called Papal Archbasilica. If I hear the words "Patriarchal Basilica" I think of the St. Mark's Basilica in Venice.
The faldstool Spellman sat in for '63 Vatican JFK Requiem.
Pope Benedict in 2007 changed the titles of the major "patriarchal basilicas" to a more simple "Papal Basilica". The Lateran of course has pride of place...hence archbasilica.I am new to this blog and I enjoy it. I look at it each day. I have recommended it many others.
Do you have more photos of the fadstool? I'm writing a little article about it for the www.salvemaliturgia.com.